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  the most anxiety-ridden thing you can do is try to design an API

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  every time i solder things i get a little tickle like "they let me do this? this is legal? I can just liquify metal in my living room?"

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  I figure that by tomorrow I may be the only person on earth with 20 light pens in a suitcase. #retrocomputing #vcfmw2026

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  Come check our talk at Saturday 10:30 AM at VCF Midwest! @mcjonestech@oldbytes.space and I will be discussing the Seequa Chameleon, a quirky PC luggable from the early 80's that had an 8088 and Z80 CPU. Come see our exhibit, too! https://geerlingguy.github.io/vcfmw21-map/#079 I'll have a collection of light pens for various systems on display, as well as a working light pen you can play with on an IBM 5150. And I'll have floppy stickers! #retrocomputing #vintagecomputing #vcfmw...

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  These pixel art floppy stickers came out great! I'll have them available at #vcfmw2026.

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  one of my few gripes with Rust's cargo build tool/package manager/floor wax/dessert topping is that there's no real great support for post-build actions like bundling or god forbid actually installing something onto your operating system enter the xtask pattern

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  This is a FastPoint Technologies (Formerly FTG) PXL-2000. It is a USB light pen interface. If you never thought USB and light pens would be mentioned in the same sentence together, well, here we are. #retrocomputing #lightpen

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  "No more features," cow's brain said, in a frustrated tone. "but I want soundblaster, and cassette, and librashader support, and..." "NO," the brain snapped, cutting them off. "How about you thoroughly test all the half-assed features you just added." "But making features is fun. Testing them is boring." The brain twitched, for it was trapped in hell

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  which way should the mac wear a scarf?

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  Once again I have become @foone@digipres.club

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  This pixel-art cow is the header of a valid DOS executable, encoded as UTF-8 Braille characters. See the whole thing here: https://github.com/dbalsom/executable_unicode/blob/main/hello_world/BRAILLE.COM Try it in DosBox! #retrocomputing #asm #x86

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  UTF-16 has issues with endianness. You have to specify if your UTF-16 encoded document is big or little endian, which you do with a Byte Order Mark or BOM, of 2-3 bytes. FE FF - Big Endian FF FE - Little Endian EF BB BF - UTF-8 UTF-8 has no endian concerns so the UTF-8 BOM has little purpose I can see other than to annoy you when you're trying to read CSVs with Python

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  Time for a new thread. I've made a short blog post outlining the basic techniques of executable emoji, which I have dubbed emojissembly. https://martypc.blogspot.com/2026/08/executable-emoji.html I started working on a general COM2EMOJI utility that I might post at some point, but let's face it the chances of me being distracted by some shiny thing in the next 48 hours is quite high.

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  i wonder if you could make a useful DOS executable with just emoji

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  i usually like staging but DosBox-X's 8088 emulation is more accurate. why am i not using my own emulator? because it's a low level emulator and i have to reboot the entire machine when i hang the CPU. which i am doing. a lot.

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  I love it when you can sort of finally congeal scattered projects together into something useful. This is a serverless, single-page x86 disassembler, that runs my marty_dasm disassembly library as wasm in your browser. It may be the only disassembler with specific, CPU-faithful architecture modes. You want to select 8088 and disassemble 0F as POP CS? Go for it. #retrocomputing #assembly #emulation

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  Nand2mario beat me to this with his really cool microcode browser https://nand2mario.github.io/8086_microcode.html but this allows me to put my own spin on it.

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  I drew the logo for the excellent Macintosh, emulator Snow. I'm not quite happy with it, though. I think it can be improved still. I think the screen needs to be 1px larger, to start. And I can improve the shading. I'm still not really happy with how it's just sitting in a random pile 'o snow. I was thinking maybe to turn it into ice, and have a reflection of the Mac in the ice, but maybe that would be too busy.

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  This is the Tandon TM100-2A. It's not the original-original OEM floppy drive for the 5150, which was the TM100-1, a single-sided drive. It's a "full height" drive, meaning it took up an entire two bays, or one entire side of the 5150's 2x2 drive bays. #retrocomputing #ibmpc #floppydisk

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  Sometimes when I buy stuff on eBay the seller throws in Other Stuff. Sometimes its cool, but I really wish they would ask first. I am now the proud owner of six c64 joysticks I didn't actually buy. It's hard to complain about free stuff except I have lots of stuff and now I have to find a home for six probably terrible c64 joysticks.

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  Sector 96 has a bad address CRC, a bad data CRC, and is deleted to boot. That is why it is Very Red.

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  Here's a FujiFilm 2" diskette, courtesy of @shayman@cosocial.ca . Thank you so much for sending it along! For a floppy disk aficionado this is a rare treat. The only compatible drive for it was sold with the Zenith MinisPort laptop. The format never caught on beyond that one model. There are some more photos here: https://www.computinghistory.org.uk/det/57098/Fuji-Film-LT-1-2-inch-Floppy-Disk/ #floppydisk #retrocomputing #vintagecomputing https://www.computinghistory.org.uk/det/80...

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  Starting to see the light at the end of the tunnel on my floppy drive controller refactor. Of course after i'm done I will have like 100 different floppies to test to make sure I didn't break anything else. My goal is to have several basic copy protection schemes working, and be able to boot all versions of Minix, with both the Tandy 1000 and PCjr able to read, write, and format floppies.

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  I have this floppy cable I want to use, but there's just one problem. Some asshole has put a twist in it.

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  so, a thought. a potential hack. maybe one for @foone@digipres.club The IBM floppy controller uses a NEC 765. The NEC 765 can support four drives, but IBM didn't really use that functionality directly. The NEC has two "Unit Select" pins intended to select a drive. For whatever reason, IBM didn't connect them, and instead added an external register called the Digital Output Register (DOR), with which you actually select the floppy drive you want to use.

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  Floppy drive sounds in MartyPC 0.4.2! Here no disk is actually in the drive - what you're hearing is the stepper motor seeking during POST in GLaBIOS. Why does the BIOS seek the drive on startup? It's trying to determine what types of floppy drive are present. If it can successfully seek past track 40, it knows it is not a standard 360K DD disk drive. #retrocomputing #emulation

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  I need a cute graphic for allowing you to shove a 3.5" disk in a 5.25" drive or vice versa. I allow this for convenience sake, but I want you to cringe while you think about it.

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  Pixel artists are relatively easy to find if you needed artwork done for a game, but I find sound designers are a lot less frequently encountered. if i wanted to commission a startup sound effect for MartyPC, maybe a second long, any idea how much that would cost, as a ballpark?

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  here i am labelling floppy drive seek sounds. i used a batch script and the greaseweazle utility to record a TEAC FD-55 seeking back and forth, starting with track 1 and 40, then back to track 2, then back to track 39. In this manner i could capture all seeks from 39 to 1 tracks. unfortunately, seeking backwards sounds different than seeking forwards, but i'm not really going to sweat that right now since i will eventualy need to redo all the sounds with an original Tandon drive, anyway....

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  the label is crying out to have "killer jamz" written on it i think